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gorann

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Everything posted by gorann

  1. IC 348 combo

    No clear skies so nothing to do but playing around with earlier data. Here is an image from my home obsy captured in November with my Canon EF 300 mm f/4 L USM telephoto lens (@f/4) to which I added data from my 5" refractor (ES 127ED @ f/5.9) sitting side by side. Totally about 10.5 hours of data: 63 x 3 min with the 300mm (Canon 60D at ISO 1600) and 55 x 8 min with the 5" refractor (Canon 60Da camera at ISO1600). Comments and suggestions most welcome Cheers, Göran
  2. IC 348 combo

    Tack Ragnar! Then I settle for the second version. And yes, it apparently has no name other than IC348 and it seems to be relatively rarely imaged but Steve Milne (@gnomus) together Olly (@ollypenrice) also had a go at it recently, but with HaLRGB and CCD down in France. I am amazed how different their image looks but I assume it is much down to the Ha and possibly also another processing approach and longer total exposure. You can see their beautiful rendition of it here: https://www.astrobin.com/326541/
  3. IC 444 and IC 443, 100D, Star 71, HaRGB

    An image to be very proud of Tim! Cheers, Göran
  4. Problems with Alnitak

    Alan, I just realized that I missed to say that you need to invert the selection after you have selected the bright stars (so you only work on the rest of the image with curves). I edited my entry above. I think my way of always avoiding stretching the stars during the initial stretching is a good way of starting any processing since you then have much less issues with stars and star shrinking later on. At least it has become a routine for me when I process. In any case (and you probably know this) it is always a good idea to do many small stretches than a few large ones in PS, since the program uses only 255 levels of brightness when you stretch while your image has over 4 billion levels (32 bit) if I got it right, so you lose less information by doing many stretches. Cheers.
  5. IC 444 and IC 443, 100D, Star 71, HaRGB

    I like the way you made the nebulosity to the left a bit more red and kept the jellyfish slightly more yellowish. Otherwise the image becomes almost only orange and black - kind of bi-coloured. With regard to the stars, what I would do is to put the original image as a layer on top of the new image (unless you have done any cropping or resizing they should align perfectly). Then you click on Add Layer Mask. Then you invert the layer mask (so the mask becomes black and your top layer becomes invisible - on Mac you press Command i to invert it). Then you use the brush tool in "white mode" to bring out the "old" stars. Probably set opacity of the tool to 25% or so and bring the stars out carefully so it looks seamless. It takes 5 min, so I could not stop myself from doing it to see how it worked on you image. By doing this you also get the stars to attain a colour that is a bit different from the nebulosity:
  6. IC 444 and IC 443, 100D, Star 71, HaRGB

    Looks good but I think something happened to the brighter stars that now have a pronounced red ring around them. I think they looked more natural in your first versions. You could use a layer mask to bring back the original versions of those stars.
  7. Problems with Alnitak

    May I suggest a third method that I use on all my images (cannot believe I invented it myself but I cannot remember where I saw it). First, I always stretch my images in Curves by doing several (ten or so) small consecutive stretches. Before each stretch I use the Select Color Range tool to select the brightest stars (putting the slider between 150 and 200). By doing this before each stretch (allowing PS to do a new selection each time, and not pressing "re-select") the selection will be a bit bigger each time (since the stretches are making the image brighter). This means that there will be no abrupt edges around the stars. Obviously it will only work if the stars in the linear image are not blown out. Here is a cropped image showing what my Alnitak looked like using this method. If you post a non-stretched version of your image, I could see if my method would work, or you could try it yourself.
  8. IC 348 combo

    When I saw the image again this morning it struck me as unneccesary dark, so I made a lighter version and also reduced some rather bloated stars while I was at it. Not sure if the lighter version is better so any comments welcome.
  9. IC 348 combo

    Thanks, much appreciated!
  10. IC 444 and IC 443, 100D, Star 71, HaRGB

    PS. you could also play with Hue/Saturation on the red
  11. IC 444 and IC 443, 100D, Star 71, HaRGB

    I used curves to bring down green a bit and bring up red (both in the middle part of the histogram on one colour channel at the time). Then I brought down the top of the RGB histogram a bit to make the stars a bit less blinding.
  12. IC 348 combo

    Thank you so much Mike, made my day (or rather night over here - and cloudy...)
  13. IC 444 and IC 443, 100D, Star 71, HaRGB

    Tim, that is really amazing data you captured, and with a DSLR. Congratulations! If I should make a personal taste suggestion I think it is still a bit green and I would prefer it a bit deeper red rather than rusty red. You could also subdue the bright stars a bit (I find them a bit blinding). Here is a quick hint of what I mean from playing with curves in PS (maybe I pushed it a bit too much towards blue). But it is just all about personal preference... Cheers, Göran
  14. This is an accidental mosaic since the framing of the Samyang moved after the meridian flip at midnight (it was sitting on my triple rig and I only adjusted the framing for the large refractor after the flip). I think it was a fortunate move since it allowed me to catch a lot of dark nebulosity above and to the left of NGC 1499 and a cute little nebula called NGC1579. Taken from my garden obsy on the Swedish countryside in Värmland on 21 Dec 2017. Temperature was ca -4°C and SQM 20.9. Camera: Canon EOS 60D (unmodded) at ISO1600. Lens: Samyang 135mm f/2 (@f/2) Mount: SW EQ8 Guiding: SW ST80 + QHY5LIIM + PHD2 Exposures: 192 x 1min = 3.2 hours Filters: None Stacked: PI Processed: PS CS5 Cheers, Göran
  15. This is the third of three images I will posts of this target for the challenge. They were all taken the same night (16-17 Dec 2917) with my new triple rig (a Samyang 135 f/2, a Canon 300 f/4 and an ES 127ED 5" refractor sitting side by side with Canon 60D cameras on them) in my garden obsy on the Swedish countryside in Värmland. Temperature fell from -7 to -14°C during the night. The ground was snow covered so SQM was around 20.5 (a bit lighter than usual) Camera: Canon EOS 60Da at ISO1600. Lens: ES 127ED (triplet apo) Mount: SW EQ8 Guiding: SW ST80 + QHY5LIIM + PHD2 Exposures: 40 x 10 min = 6.7 hours Filters: None Stacked: PI. Processed: PS CS5. Cheers, Göran
  16. This is the second of three images I will posts of this target for the challenge. They were all taken the same night (16-17 Dec 2917) with my new triple rig (a Samyang 135 f/2, a Canon 300 f/4 and an ES 127ED 5" refractor sitting side by side with Canon 60D cameras on them) in my garden obsy on the Swedish countryside in Värmland. Temperature fell from -7 to -14°C during the night. The ground was snow covered so SQM was around 20.5 (a bit lighter than usual) Camera: Canon EOS 60D (unmodded) at ISO1600. Lens: Canon EF 300mm f/4 L USM (@ f/4) Mount: SW EQ8 Guiding: SW ST80 + QHY5LIIM + PHD2 Exposures: 134 x 3 min = 6.7 hours Filters: None Stacked: PI. The image is a mosaic of two frames that have a 50% overlap in the centre of the image Processed: PS CS5. I have added a small amount of data to the tadpoles taken taken with the 5" refractor in Feb 2017 (which may disqualify the image but I leave that to the judges) Cheers, Göran
  17. This is the first of three images I will posts of this target for the challenge. They were all taken the same night (16-17 Dec 2917) with my new triple rig (a Samyang 135 f/2, a Canon 300 f/4 and an ES 127ED 5" refractor sitting side by side with Canon 60D cameras on them) in my garden obsy on the Swedish countryside in Värmland. Temperature fell from -7 to -14°C during the night. The ground was snow covered so SQM was around 20.5 (a bit lighter than usual) Camera: Canon EOS 60D (unmodded) at ISO1600. Lens: Samyang 135mm f/2 (@f/2) Mount: SW EQ8 Guiding: SW ST80 + QHY5LIIM + PHD2 Exposures: 360 x 1min = 6 hours Filters: None Stacked: PI. The image is a mosaic of two frames that have a 50% overlap in the centre of the image Processed: PS CS5 Cheers, Göran
  18. california to 7 sister

    Yes, great start! I do wonder why you had the camera at ISO 12800. That will introduce noise. I never go above 1600 with my EOS 60D (I use 12 800 for the framing before I start exposing). Maybe you stopped the lens down a lot? If you have it around f/4 then you can use ISO1600 and 3 min exposures on this object. Cheers
  19. Collaborative imaging

    I do not see Hubble as a major competitor. It has many users and they are mostly after very specific data and are very rarely aiming for pretty pictures. We amateurs are often targeting more wide field objects than Hubble, and there we will win every time with our short focal lengths. We would be beaten every time on distant galaxies but in wide field we could probaly achieve some unprecedented images if we combined our data - we could go for 1000 hours at FL 500mm on NGC7000, for example (although someone is likely to burn his/her CPU trying to stack that data)
  20. Sorry for the late reply. I would think that many regard TS as a quite serious supplier of medium to high quality gear. Like Skywatcher, the more expensive models are probably about as good as it gets (like the Esprits). I am myself looking for a good 5" refractor and I recently e-mailed them this question: "How does the APO130f7-P compare optically to the APO130f6. I am puzzled by the large price difference." and the answer was: "The Apo130f6 has a completely different triplet lens with better color and off axis correction. It also has a higher quality and larger focuser." So, I assume you get what you pay for also there. The less expensive models are probably at least as good as the Explore Scientific scopes.
  21. Is there a reason why you did not include the large TS line of small refractors in your list? I would seriously consider some of them: https://www.teleskop-express.de/shop/index.php/cat/c223_APO-Refractor-Telescopes.html Cheers Göran
  22. Thanks, much appreciated! Just started the celebration....😉
  23. This is 142 x 1 min exposures with the Samyang 135 f/2 from last Saturday where I have added data to the nebulae from my ES 127ED refractor (30 x 6min) and Canon 300 f/4 (59 x 3min) sitting next to each other on my triple rig. All connected to Canon EOS 60D cameras (60Da on the large refractor). Stacked in PI and merged and processed in PS. So altogether about 8 hours of data collected during three hours. There was not really enough data from the larger lenses to make presentable images on their own but they were good enough to add to what was collected by the little Samyang - at f/2 you do not need that many hours (or do you? Olly @ollypenrice may have a comment about that and the f-ratio myth). I also post a crop turned 180° that shows the Ghost in perhaps a more familiar direction If you want to read about all my troubles that night and suggestions from SGL friends about how they can be solved you can look at my previous post: Comments and suggestions most welcome Cheers Göran
  24. Thanks Spock! Thanks Olly, it is Saturday evening and cloudy so there is not much more to do than celebrate! I spent a few hours now on trying to make a presentable image out of the 5" refractor data of the Ghost. Only 30 x 6 min under a moonlit sky, but that is what I've got:
  25. Yes, I finally found it that night! Thanks!
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